In order to understand how it came about that the British infantry within a few years proved more than a match for the French in the Peninsular War, it is necessary to have some knowledge of the methods of fighting previously adopted by the armies of the two nations, and then to see how Moore altered these methods, by assimilating the good and by eliminating the bad, by pruning and by inducing fresh growth. We shall see that, in the new system of training, everything depended on the regimental officer; and we shall see that, when war came, it was the regimental officer who made the British army almost invincible.

Without entering too deeply into the history of tactics, we may say that up to the middle of the eighteenth century the fighting formation of infantry, whether in attack or defence, consisted generally of solid bodies of troops, which marched up in two massive columns, and then deployed, in the face of the opposing force, into two lines each composed of three ranks. Skirmishers were then unknown; and very great attention was paid to drill. About 1757 we find the Austrians using light troops (Croats) to harass Frederick the Great's army on the march; but these do not appear to have been properly organised, and, though always annoying, they seldom acted with real judgment. In 1774 Mesnil Durand invented a system in which skirmishers played a considerable part. Battalions were to move in double company columns at deploying intervals, two of the ten companies of each battalion acting as skirmishers to cover the whole front of the line of columns. It was held that in this way the fire of the skirmishers would make itself felt to such an extent that it would only remain for the heavy columns behind to push in and crush the enemy by sheer weight. This was to a certain extent the system adopted by the French in 1793, and employed by the French generals in the Peninsular War, and by Napoleon until his final defeat at Waterloo, except that the columns of attack were deep and solid, and not merely single battalion columns or lines of battalion columns.

It may therefore be said that skirmishers first took their place in the organisation of Continental armies about 1774, but years before that the question of their employment had been freely discussed. As early as 1754 Comte Lancelot Turpin de Crissé had published a work on the Art of War, in which he dealt with the uses of light troops at some length, and the British army had had its bodies of trained light infantrymen certainly before 1758.[41] In all probability they originated about the year 1757, when the British generals, fighting against the French in America, found that the latter's Red Indian allies perpetually annoyed them on the march and on other occasions, and determined to meet them in their own methods of fighting. Consequently, every regiment in America was ordered to select "the most enterprising officers and the most active of the privates with the appellation of Rangers." Lord Howe, then commanding the 55th Regiment, but in 1758 raised to the command of the army in the field, was immensely impressed by the Red Indian methods of warfare, and was supported by several commanding officers, who realised the absurdities of tight clothes and movements in solid formation, when engaging the enemy in the rough forest country of the New World. The success which attended the experiment of the Rangers led to the formation of a light company in every regiment, and the valuable services which these companies performed during the next few years fully justified their existence. And the matter was carried still further, for, in 1758, a whole regiment was equipped for light work, and named Gage's Light Infantry.[42] In that year, however, while leading a desperate attack on the French, Howe was shot dead, at the head of the Rangers, in the hour of victory.

At the peace of 1763 all the light companies of regiments were reduced, and the lessons learned in America for the time being were forgotten. In 1770, however, some one remembered the value of light troops, and the light companies were established afresh. In all probability that some one was Lord Howe's brother, General William Howe, who had distinguished himself as a leader of light infantry in Wolfe's Quebec campaign of 1759, for in 1774 he was allowed to take the light companies of seven regiments to Salisbury, and exercise them as a battalion in certain manœuvres which he had invented. There was apparently little similarity between Howe's formations and those of Mesnil Durand mentioned above, for whereas the latter's flank companies were employed with their own battalion, as part and parcel of it in the fight, Howe's idea was to take these companies away from their regiments, and form them into separate battalions, for distinct and special work. In this way Sir William Howe, in chief command of the British forces, employed the flank companies of regiments during the War of American Independence, the most important and most hazardous duties being performed by battalions composed of them.

Both Viscount Howe and his brother, Sir William, gained their first knowledge of light troops from the Red Indians, and it may perhaps be remarked that, in 1880-1881, irregular warfare with the Boers gave us the idea of mounted infantry. There is a striking analogy between the old light infantry and the modern mounted infantry: each was the outcome of a desire for greater mobility than ordinary infantry soldiers were capable of; each began in the same way; the light company and the mounted infantry company contained the picked men of the battalion, and, in war, these companies of the best men were taken away from their regiments to work, with similar companies of other regiments, as separate battalions, the merits or demerits of which it is not necessary to enter into here.

To return to the development of light troops in the British army. In 1782 the light companies of nine regiments were assembled in camp at Coxheath, Kent, and, together with two battalions of infantry and two regiments of light dragoons, were practised in what was termed the "Dundas Exercises," which were being tried for the first time. A year or two later, Dundas visited the Prussian manœuvres, obtained some fresh ideas, and then published his monumental work, which eventually became the first drill-book authorised to be used in the British army. Dundas, however, had very little new to say about light troops, and his exercises were practically on the Continental model. In 1794 Sir Thomas Graham[43] (afterwards Lord Lynedoch) raised a regiment (which was numbered the 90th), and had it equipped and drilled as a light infantry corps, though it was not recognised officially as such for another eleven years. It was in the above year that Moore was working with Corsican troops in the field, and he always considered the Corsicans the best light infantrymen in the world, although he acknowledged that they lacked the discipline necessary for holding their own against highly-trained troops. In 1798 Howe[44] again came to the front, and superintended the training of a brigade of all arms, assembled on the Essex coast, in his light drill. Lastly, in 1800, H.R.H. the Commander-in-Chief ordered the assembly at Horsham of a temporary corps, for the purpose of training a body of men in the use of the rifle, fourteen regiments being called upon to furnish thirty privates and a proportion of officers and non-commissioned officers. After the summer training, these men were moved to Blatchington, and were then formed into the Rifle Corps (95th),[45] for whom Colonel Coote Manningham and Lieutenant-Colonel the Hon. W. Stewart drew up the famous 'Regulations for the Rifle Corps,' published in 1801. The methods of training these riflemen were very similar to those employed in training temporary light infantry corps composed of the light companies of regiments, except in so far as the superior range and accuracy of the rifle over the flintlock musket altered the conditions of the attack and defence.

By this time it had been discovered that Napoleon had developed the use of his voltigeurs enormously, and that his victories were being secured by the judicious employment of these light troops; so English books dealing with the systematic training of light troops now began to appear. The earliest of these was one based on a translation of a work by a "German officer of distinction and of much military experience," which, first produced in 1798 (reprinted in 1801 and 1803), under the title of 'Regulations for the Exercise of Riflemen and Light Infantry, and Instructions for their Conduct in the Field,' was ordered to be studied by all officers of the army. Who that German officer was is never made clear, and in 1803 there appeared another and a far more valuable work, entitled 'A Treatise upon the Duties of Light Troops,' translated from the German of Colonel Von Ehwald, but there is nothing in this book to lead one to believe that Von Ehwald was the author of the earlier work. The gallant Colonel had served in the Seven Years' War, commanded a corps of Hessian jägers, in British pay, during the American War of Independence, and subsequently commanded a light corps of the Danish army, and his book contains a mass of useful information on the training of light troops, as well as examples of their work in the field during several campaigns.

Judging by the contents of this treatise, it is more than probable that Sir John Moore had studied it in the original, for Von Ehwald's ideas on discipline and training were identical with those upon which Moore subsequently set to work. Both Von Ehwald and Moore held the opinion that an army which could place in the field large numbers of light troops, so highly trained and disciplined as to be capable of working intelligently in extended order in more or less independent small parties, would be able to outflank, outmanœuvre, and defeat an enemy of superior strength who adhered to close formations. Rapidity of movement, however, and the ability to make good use of ground as well as of their firearms, were essential to the success of light troops, and Moore knew that unless there could be produced a higher standard of discipline than was yet known in the British army, it would be impossible to create light troops of any value. And Moore's ideas of discipline differed somewhat from those of most officers of the time, in that he did not believe in the "mechanical discipline" which made a mere automaton of the soldier, but rather in that "intelligent discipline, best illustrated, perhaps, by a pack of well-trained hounds, running in no order, but, without a straggler, each making good use of his instinct, and following the same object with the same relentless perseverance."[46] In his determination to establish this new form of discipline lay Moore's success, and he always maintained that by no other means than by inculcating the strictest habits of intelligent discipline in all ranks could self-reliance and initiative come natural to a body of troops. Whether he discovered this for himself, or whether he learned it from Von Ehwald, or whether, again, both of them were following the lead of Napoleon, whose skirmishers had already made their mark in European warfare, the fact remains that Sir John Moore was the first person to attempt to apply it to a large number of British soldiers, and he was the first person to succeed.

In the summer of 1803, therefore, Moore commenced work with his famous brigade at Shorncliffe Camp, and he decided to train his brigade as light troops, not in the usual way by extemporising battalions out of light companies detached from various regiments, but by employing whole regiments. For this purpose the 52nd and the 43rd were, in 1803, formed into light infantry regiments, and, together with the newly raised Rifle Corps (95th), handed over to Moore to train. He began at the beginning, and thoroughly overhauled the existing regimental systems; he went deeply into interior economy, and instituted many reforms—so far-reaching and excellent that they have remained almost unaltered to the present day. He insisted that discipline could only be maintained by the officers of all ranks always being in touch with their men, and ever having their welfare at heart. A hard worker himself, he saw that all the officers of his brigade worked hard also; and during the training seasons at Shorncliffe the officers were seldom off duty on week-days, and had to brush up for the General's inspection on Sundays, for Moore did not recognise any necessity for recreation. On one occasion the father of a young officer wrote to the General to say that he proposed to send his son a horse. Moore's reply was characteristic: "that he should be very pleased that the horse should be sent, but that it would be necessary for the father to send with it some one to ride it, for his son would have no time to do so."[47] His first care was to have efficient officers; he watched them carefully, and he got rid of those whom he deemed useless for his purpose, thus laying the foundation-stone of the future building. With good and reliable officers, establishing a chain of responsibility from highest to lowest, with a thorough organisation of battalions on the company system, with non-commissioned officers and men no longer ruled with a rod of iron, but respecting and relying on their officers, Moore began to see his way clear.